Module systems



Sept 30, 1969 R. c. swENGEL, SR 3,469,448

MODULE SYSTEMS Original Filed Oct. 26, 1959 United States Patent() 3,469,448 MODULE SYSTEMS Robert Charles Swengel, Sr., Hellam, Pa., assignor to AMP Incorporated, Harrisburg, Pa. Original application Oct. 26, 1959, Ser. No. 848,568. Divided and this application Mar. 24, 1967, Ser. N o.

Int. Cl. G01k 11/12 U.S. Cl. 73-356 3 Claims ABSTRACT OF THE DISCLOSURE Cross-references to related applications This application is a division of my earlier copending application Ser. No. 848,568 filed Oct. 26, 1959, entitled Module Systems.

Brief description of the drawing FIGURE 1 is a perspective View of a modular circuit unit incorporating the teachings of the present invention; and

FIGURE 2 is a top plan view of the unit of FIGURE l showing further details of the invention.

Description of the preferred embodiment The attainments of the present invention will become apparent to those skilled in the art upon a reading of the following detailed description when taken in conjunction with the drawings in which there is shown and described an illustrative embodiment of invention; it is to be understood, however, that this embodiment is not intended to be exhaustive nor limiting of the invention but is given for purpose of illustration in order that others skilled in the art may fully understand the invention and the principles thereof and the manner of applying it in practical use so that they may modify it in various forms, each as may' be best suited to the conditions of a particular use.

Various proposals for packaging functional circuits or subcircuits in modular form have been advanced, mainly because of the attractiveness of space savings through the compaction offered by the building block technique, or cost savings posed by the possible automated production of the modules, or time sav-ings in maintenance and repair by virtue of the more readily tracing and replacement of a failed circuit. The present invention provides a module box in which the circuit components of the modular unit or cell are contained, two opposite sides of the box having a series of channels regularly spaced according to a predetermined center-to-center grid spacing system. All or preselected ones of the channels have recessed elongated sockets which are connected to the terminal points of the module circuit components and adapted to receive a contact blade endwise in a sliding frictional engagement. A wiring framwork for interconnecting the module boxes includes a base panel and a series of sidewall panels between pairs of which rows of module boxes are arranged to be plugged. Printed circuitry lines, lengthwise extending and regularly spaced across the width of the sidewall panels, serve as the intermodule wiring. A series of parallel and regularly spaced blades transversely ice mounted edgewise on the sidewall panels provide for circuitry continuity from the sockets to be printed circuitry lines of the sidewall and base panels by integral tines arranged for selective connection with the printed circuitry. For a complete description of one interconnection system in which the principles of the present invention may be employed, reference is made to applicants above-identified copending application.

There is shown in FIGURES l and 2 a module unit 10 which may have incorporated therein various electrical components such as resistors, condensers, coils, transistors, diode devices, transformers and the like forming an electrical circuit or subcircuit of a larger circuit network. The module unit may be plugged into a wiring framework which serves as the means for interconnecting the modules and for connecting the modular array to extenral circuitry or other modular arrays. A series of channelshaped contact members 12 are disposed on opposite sidewalls of the unit 10 and provide means for connecting the unit 10 with mating contact members on a wiring framework. The contacts 12 have tabs 14 secured at an end thereof. The various electrical components 16 are disposed within the central portion of the unit 10 and are electrically connected to the contact tabs 1.4 by means of the conductors 18. Preferably the unit 10 has an integral bottom so that it can act as its own mold where it is desired to have a completely encapsulated and hermatically sealed unit, the potting compound, such as a suitable epoxy type resin, simply being poured into the box after the components have been positioned with their leads 18 electrically attached to the contacts 12 of the module.

Subdividing and packaging complex electrical circuits according to function into a series of modular units simplies the tracing of component failures through analysis of circuit malfunction. Frequently, however, a more ready identification of component failure is desired, especially in connection with those module units incorporating components having a normal operating temperature in any substantial degree more than ambient temperature. In order to incorporate temperature sensitive detection means advantage may be taken of materials such as the tin salt of 4-methyl-1,2-dimercaptobenzine dispersed in a suitable carrier lacquer, which exhibits a self-recoverable color variation in response to temperature. In use, a narrow strip or coating 20 of such material is tirst applied to an exposed surface of the module units during, for eX- ample, the factory pretesting of the units or otherwise. While the unit is satisfactorily running at its operating temperature the color assumed by the temperature sensitive material is noted. Adjacent thereto a second strip or coating 22 of a temperature insensitive material such as a paint or dye is then applied. The color of this temperature insensitive material matching the observed color of the temperature sensitive strip. Any deviation between the colors of the two strips in later service of the module unit gives a visual indication of any operation above or below the normal temperature and possible failure.

Changes in construction will occur to those skilled in the art and various apparently different modifications and embodiments may be made without departing from the scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only.

I claim:

1. In a modular circuit unit for incorporation in an electrical system, said unit including at least one heat generating component and having a readily exposable surface when incorporated in said system, a first agent disposed on said surface and variable in color in response to the temperature of said unit, said first agent comprising the tin salt of 4-methyl-1,2-dimercaptobenzine, a second agent substantially invariable in color disposed on said surface adjacent said first agent, the color of said second agent being substantially matched to the color assumed by said first agent when the unit is running at its normal operating temperature.

2. In a modular circuit unit for incorporation in an electrical system, said unit including at least one heat generating component and having a readily exposable surface upon incorporation in said system, said unit having a normal operating temperature substantially above ambient temperature, a heat sensitive agent disposed on said exposable surface and having a variable visible characteristic responsive to the temperature of said unit, the visible characteristic of said heat sensitive agent at said normal operating temperature being different than the visible characteristic of said heat sensitive agent at temperatures above or below said normal operating temperature, and a heat insensitive agent disposed on said surface adjacent said heat sensitive agent and having a visible characteristic substantially matched to the visible characteristic assumed by said heat sensitive agent when the unit is running at said normal operating temperature.

3. In a modular circuit unit for incorporation in an electrical system, said unit including at least one heat generating component and having a readily exposable surface upon incorporation in said system, said unit having a normal operating temperature substantially above ambient temperature, a rst agent disposed on said exposable surface and variable in color in response to the temperature of said unit, the color of said rst agent at said normal operating temperature `being different than the color of said rst agent at temperatures above or below said normal operating temperature, and a second agent substantially invariable in color disposed on said surface adjacent said first agent, the color of said second agent being substantially matched to the color assumed by said first agent when the unit is running at said normal operating temperature.

References Cited UNITED STATES PATENTS 1,330,570 2/1920 Aronson 73-356 1,924,793 8/ 1933 Laske 116-114.20 2,809,116 10/ 1957 Laskowsk'i 7.3--356 LOUIS R. PRINCE, Primary Examiner DENIS E. CORR, Assistant Examiner 

